That's the basic contradiction in modern human societies. Democracies always get taken over by the oligarch class, while dictatorships only work as long as the leaders stay honest and sane. IDK what China is doing to ensure good leadership, but it's worked for 50 years now. Where is your evidence that "Fewer heads always deliver worse decisions?" I would strongly challenge that. If our access to information wasn't so tightly controlled and distorted, it would be true. But millions of heads filled with Fox News/ CNN propaganda are worse than two or three who can actually think for themselves.